Multipoint or lift lever locks are fitted in uPVC, composite and wooden doors. The way that they operate is different from traditional locks as the handle engages all of the bolt work in the mechanism before it is locked with a key Unless the lock is well aligned and working smoothly, this can put an enormous amount of pressure on the centre lock case and in most cases this is what will cause the lock to fail. Errington Locksmiths in Milton Keynes supply, fit and service all makes of multipoint locks suitable for uPVC, composite and wooden doors including: